This invention relates to new and novel anionic living polymers and their derivatives. More specifically, it relates to anionic living polymers produced from methacrylic acid esters having acetal or ketal group and derivatives therefrom.
This invention relates to new and novel curable composition containing these polymers.
There has been no report of producing anionic living polymers directly from methacrylic acid ester monomers, containing at least one hydroxyl group within one molecule, because of presence of active hydrogen within the methacrylic acid ester itself.
The known method for obtaining polymers of hydroxyl group-containing methacrylic acid ester based on anionic polymerization is as follows (JPA 1986-250011):
As a precursor for a polymer of a hydroxyl group-containing methacrylic ester, an anionic living polymer having protected hydroxyl groups is produced by polymerizing methacrylic acid ester having a substituted silyl group-protected hydroxyl group (that is, the hydroxyl group is protected by a substituted silyl group as a silyloxy group) in the presence of an anionic polymerization initiator.
However, the yield of an anionic living polymer is very low when such methacrylic acid ester having silyl group-protected hydroxyl group is anionically polymerized using potassium tert butoxide as a polymerization initiator (referred to as initiator).
Evidence for such problem was published in "YUKI-GOUSEI KAGAKU KYOUKAISI (JAPAN)", page 147, vol. 44, 1986, which reported, in part, that anionic polymerization using methacrylic acid ester with silyl group-protected was inefficient.